DESIGN OF THE LEP MAIN RING WIGGLERS

It is proposed to install eight three-pole wiggler magnets in the LEP main ring at CERN, in order to provide a means both for decreasing the damping time at injection and for controlling the horizontal beam emittance. The possibility of having polarized beams at LEP is retained by the choice of a field in the end gaps which is only 40 % of that in the central gap, the pole lengths being chosen to keep the field integral zero. The paper describes the design of the magnet, its excitation requirements and its performance as predicted by three-dimensional magnetic field computations